A human rights group has criticised UN Secretary General Ban Ki-moon for failing to raise human rights issues at talks with China's President Hu Jintao.
The New-York based Human Rights Watch had urged Mr Ban to publicly express concern about the imprisonment of Nobel Peace Prize winner Liu Xiaobo.
It said Mr Ban's silence was shocking and sent a chilling message to Chinese rights activists.
Mr Ban's spokesman confirmed the matter was not discussed at Monday's talks.
The spokesman said the question of human rights did not come up even in a meeting with President Hu.
He said the two had discussed a wide range of issues, and Mr Ban had asked Beijing to play a greater role in solving African conflicts such as those in Somalia and Sudan.
Activists had already criticised the secretary-general for his cautious response when Liu Xiaobo was awarded the Nobel Peace Prize last month.
Mr Ban then offered only indirect praise for the jailed dissident then, and did not call for his release.
The UN chief has defended his low-key style by saying he likes to exercise quiet diplomacy.
But commentators say he has to tread carefully, since he needs China's support to win a second term in office.
That is because it is one of the five powerful UN Security Council members which wields a veto.
HRW said if this was indeed the secretary-general's calculation, he should remember that his relevance in the post depended on being a clear and courageous voice on human rights.